Additional sockstat(1) arguments/functionality

[Chris Ross <cross+netbsd%distal.com@localhost>]

  I am using a software package that is principally a linux suite,  
but understands "BSD" as something else that exists.  In this case, it  
uses sockstat(1) to provide information that apparently it obtains  
from netstat(1) on Linux systems.

  However, it uses the -P argument to [FreeBSD's] sockstat(1).  In  
looking at the man page for FreeBSD's sockstat, I see there are a  
couple of options that NetBSD's sockstat(1) doesn't have, and also a  
couple of options in NetBSD's that are missing from the one in  
FreeBSD(1).

  The short question is, the -P argument allows one to specify one or  
more protocols to limit the output to.  So, if you are interested in  
TCP sockets, and not UDP sockets, you can simply specify "-P tcp" on  
the command-line.  This seems a useful feature to have in our  
sockstat(1), but I wanted to check with a larger user-base for opinion.

  I'd be happy to submit a patch to add said functionality unless  
someone thinks it would be a bad idea.

  Thanks.  All feedback welcome.

                                  - Chris